[XFS] Remove a no-longer-correct debug assert from dio completion

handling.

SGI-PV: 955302
SGI-Modid: xfs-linux-melb:xfs-kern:26804a
Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>

fs/xfs/linux-2.6/xfs_aops.c

@@ -1356,7 +1356,6 @@ xfs_end_io_direct(
 		ioend->io_size = size;
 		xfs_finish_ioend(ioend);
 	} else {
-		ASSERT(size >= 0);
 		xfs_destroy_ioend(ioend);
 	}